Fundamentals and enabling technologies to enter the upper limits okhotnikov, oleg g. The tdcf amplifier was first conceived and demonstrated at tampere university in the research group of professor oleg okhotnikov in 2008. In such lasers, the pump is not confined within the cladding of the fiber, but instead pump light is delivered across the core multiple times because it is coiled in on itself. We demonstrate that resonant highmodulationdepth saturable absorbers allow efficient pulse shortening in qswitched lasers. Tapered double clad fiber laser 0 200 400 600 800 1200 0 100 200 300 400 500 600 w launched pump power 915nm, w. By analogy to dispersion management, we refer to this scheme as nonlinearity management. A fiber laser is a laser in which the active gain medium is an optical fiber doped with rareearth. Osa passively synchronized twocolor modelocked fiber.
Sep 01, 2004 980nm picosecond ytterbium fiber laser 980nm picosecond ytterbium fiber laser karirinne, suvi p grudinin, anatoly b okhotnikov, oleg g. I would like to thank my supervisor, professor oleg okhotnikov for his professional. A high power mopalaser based on a modelocked thuliumdoped. Okhotnikov, semiconductor saturable absorber mirror with wavelength. Okhotnikov, thermal management in longwavelength flipchip semiconductor disk lasers, ieee journal of selected topics in quantum electronics, 21, 6, 336, 2015.
May 15, 2012 tunable singlelongitudinalmode ytterbium all fiber laser with saturableabsorberbased autotracking filter. Fiber lasers kindle edition by okhotnikov, oleg g download it once and read it on your kindle device, pc, phones or tablets. Costeffective fiber lasers for material processing. A passive modelocked linearresonator fiber laser using polarizationmaintaining fibers and a saturable absorber to produce ultra short pulses and a longterm reliable operation with reduced maintenance. The technology was granted a patent in 20 as a means to overcome the nonlinear optical effects which previously limited the powerscaling of fiber lasers and fiber amplifiers. Waferfused 0 and 1550nmwaveband vertical external cavity. Author publications 50 proceedings article 27 april 2016. From microresonators to fiber lasers philippe grelu by recirculating light in a nonlinear propagation medium, the nonlinear optical cavity allows for countless options of light transformation and manipulation. Chamorovskiy, jussi rautiainen, antti rantamaki and oleg g. Semiconductor disk lasers for the generation of visible and. Okhotnikov abstractusing semiconductor saturable absorber mirrors and a gratingpair dispersion compensator, we obtain reliable selfstarting mode locking of a ytterbium yb fiber laser tunable over 125 nm. Optical amplifiers and lasers based on tapered fiber geometry for power and energy scaling with low signal distortion valery filippov, yuri chamorovskii, konstantin golant, andrei vorotynskii, oleg okhotnikov.
Lasers operating in the 0 and 1550nm wavelength band, capable of producing high output power that can be coupled into singlemode fibers, are of considerable interest for nextgeneration fiber lasers and amplifiers. Highrepetition rate modelocked ytterbium fiber laser using. Pdf raman fiber oscillators and amplifiers pumped by. The very high peak power that can be achieved with femtosecond pulses means that in. First we describe a map that can be regarded as a combination of nonlinearity management and dispersion management. A fbg consists of a periodic change in the refractive index of a fiber core. Among them, timing jitter, which is an important criterion for a good harmonic modelocking, is rarely discussed in harmonic modelocking of tmdoped fiber lasers. Since 1999 he has been a fulltime professor at optoelectronics research centre, tampere university of technology. We propose the use of selfdefocusing nonlinearities to control nonlinear phase shifts in soliton fiber lasers. Featuring contributions from leading fibre laser scientists such as oleg okhotnikov, andreas tunnermann, philip russell, frank. Compact laserdiodebased femtosecond sources c t a brown, m a cataluna, a a lagatsky et al.
Use features like bookmarks, note taking and highlighting while reading fiber lasers. Using a 70% modulation depth resonant saturable absorber mirror we achieved 8 ns pulses that are close to the limit set by the cavity length and are, to our knowledge, the shortest pulses demonstrated to date from passively qswitched fiber lasers. A buttcoupled sesam provided reliable selfstarting at a pump power of 150 mw. Optical amplifiers, modulation, amplifiers, fiber lasers, wave propagation, ytterbium, picosecond phenomena, q switched lasers, laser optics, absorption. Passively qswitched tmhodoped fiber lasers operating at 2. Saarinen, jari lyytikainen, juuso heikkinen, juha m. Another wellknown alternative is a gires tournois interferometer gti. Modeling and technologies of ultrafast fiber lasers brandon g. The all fiber design using dichroic fiber mirror combined with photonic bandgap fiber dispersion compensator is highly stable and requires virtually no alignment. However, we note that timing jitter is provoked by the cavity and pumping instabilities, and therefore in case of freerunning passively mode. Due to enhanced nonlinear interaction in the fiber, noise free pulselocking was achieved allowing for a cavity mismatch tolerance of 140. The approach taken in this thesis relies on using modelocked fiber lasers as pump sources for frequency. Technology, systems, and applications, 823701 21 march 2012.
Fiber technology offers a rich supply of compact and maintenance free lasers delivering ultrashort pulses in a broad wavelength range. Using a master slave configuration, a robust synchronization was achieved for twocolor erbium and ytterbium modelocked fiber lasers. Tunable singlelongitudinalmode ytterbium all fiber laser. Pulse operation has been achieved for both anomalous and normal dispersion of the. My deepest gratitude goes to my supervisor, professor oleg okhotnikov, for is invaluable. Another type of fiber laser is the fiber disk laser. Most of the demonstrations have been based on passive modelocking using semiconductor saturable absorber mirrors sesams as modelockers 9,10,11,12. Ultrafast fibre laser systems based on sesam technology.
A strong impact of a new effect dynamic gain induced pulse shortening, on the duration, repetition rate and energy of a qswitched fiber laser was studied. This approach, however, is generally not suitable for fiber lasers, because fiber cavities tend to exhibit dispersion larger than a gti can compensate for. Due to the relatively less study and unique properties of tmdoped fiber lasers, there remains to be unexplored features of harmonic modelocking in tmdoped fiber lasers. This is the highest tolerable cavitylength difference ever been obtained for synchronized modelocked oscillators. Recent citations graphenews2 heterostructure saturable absorbers for ultrashort pulse generation in lband passively modelocked fiber lasers wenxiong du et al. A modelocked linear fiber laser cavity with enhanced pulsewidth control includes concatenated sections of both polarizationmaintaining and nonpolarizationmaintaining fibers. However, ultrashort pulses in the visible and uv domains are difficult to obtain directly from fiber lasers.
This letter describes a technique for realizing a gold au surface with roughness at the atomic scale using techniques compatible with integrated device fabrication. In addition to cw bismuthdoped fiber lasers, modelocked lasers operating at all major wavelengths covered by cw bismuth fiber lasers have been demonstrated. In fiber lasers of only a few cm length we obtained up to 10 w of cw output power, diffraction limited beam profiles at 4 w cw operation, 1. Ultrafast fiber lasers using novel semiconductor saturable.
Trends in optical fibre metrology and standards oliverio d. Okhotnikov, dispersion compensation free fiber laser modelocked and stabilized by highcontrast saturable absorber mirror, ieee journal of quantum electronics, vol. Optoelectronics research centre at tampere university of technology prof. The 1990s shows an increased expansion of optical fibre networks which respond to the rapid growth on a world scale of. The au layer is electronbeam evaporated on a selfassembled monolayer of 3mercaptopropyl trimethoxysilane on an oxidized silicon substrate and shows a rootmeansquare surface roughness of. Okhotnikov gratings fbgs have opened the opportunity for the development of a large variety of optical fiber sensors and of fiber telecommunication devices, also 1. The modelocked laser produces 572fs soliton pulses at 571. Optoelectronics research centre at tampere university of. Passively synchronized erbium 1550 nm and ytterbium 1040nm modelocked fiber lasers sharing a cavity matei rusu, robert herda, and oleg g. Fiber lasers wiley online books wiley online library. Since 1999 he has been a fulltime professor at optoelectronics research centre, tampere u.
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